"On my putt it was quite an advantage that I had the similar putt earlier, just a little bit longer, but pretty much the same line and I knew it didn't break as much as I thought. So that helped me a lot. It was a good stroke and so it went in.

"But I was surprised about him, obviously, you don't want to win a golf tournament that way. Of course I will take it, but you don't really want the other guy missing a short putt."

Watson added: "I thought I hit a great putt. There's no way that ball should go that way, unless it's wind forced. It's just one of those things. It was Martin's time and not my time."

Watson also held a two-shot lead with two holes to play following birdies on the 14th, 15th and 16th, only to drive into water on the 17th and run up a bogey six, while Kaymer birdied the same hole.

World No 1 Rory McIlroy, who won the Open Championship and US PGA this year, struggled to a 75 to finish two over par, one ahead of Jim Furyk.